The present invention relates to thermoplastic molding compositions made from
A) from 20 to 98% by weight of a particulate graft polymer made from
a1) from 30 to 90% by weight of an elastomeric graft core made from
a11) from 80 to 99.99% by weight of a C1-C10-alkyl acrylate,
a12) from 0.01 to 20% by weight of at least one crosslinking monomer, and
a13) from 0 to 19.99% by weight of one or more other monomers,
a2) from 10 to 70% by weight of a graft shell made from
a21) from 50 to 100% by weight of a styrene compound of the formula I 
xe2x80x83where R1 and R2 are hydrogen or C1-C8-alkyl and n is 0, 1, 2 or 3,
a22) from 0 to 50% by weight of at least one monoethylenically unsaturated nitrile compound, and
a23) from 0 to 40% by weight of one or more other monomers,
B) from 0.5 to 78.5% by weight of a thermoplastic polymer made from
b1) from 50 to 100% by weight of a styrene compound of the formula 
xe2x80x83where R1 and R2 are hydrogen or C1-C8-alkyl and n is 0, 1, 2 or 3,
b2) from 0 to 50% by weight of at least one monoethylenically unsaturated nitrile compound, and
b3) from 0 to 40% by weight of one or more other monomers,
C) from 1 to 79% by weight of a copolymer made from
c1) from 30 to 90% by weight of styrene and/or xcex1-methylstyrene,
c2) from 10 to 70% by weight of butadiene, and
c3) from 0 to 30% by weight of one or more other monomers
in which all, or virtually all, of the olefinic double bonds have been hydrogenated, and
D) from 0.5 to 30% by weight of a copolymer made from
d1) from 50 to 100% by weight of isobutene, and
d2) from 0 to 50% by weight of one or more other monomers.
The invention further relates to the use of these molding compositions for producing films and moldings, and also to films and moldings made from these molding compositions and to a process for preparing the molding compositions.
The total of components A) to D) is, of course, 100% by weight.
There are many application sectors for plastic films. They are mostly produced by calendering or extrusion.
EP-A 526 813 has disclosed thermoplastic molding compositions made from a highly crosslinked acrylate rubber with a graft shell made from methyl methacrylate or styrene/acrylonitrile and with a partially crosslinked acrylate rubber and with an ethylene/vinyl acetate copolymer, and also if desired with another polymer based on styrene and/or acrylic compounds. Under the conditions of molding, for example to give films, these compositions tend, however, to give undesirable discoloration.
DE-A 42 11 412 has proposed, as a film material, mixtures of styrene/acrylonitrile polymers and thermoplastics, which have a graft shell made from an elastomeric polymer. However, the process for preparing graft polymers of this type is complicated and it is therefore difficult to obtain consistent product quality.
EP-A 708 145 has disclosed thermoplastic molding compositions which comprise an acrylate rubber with a graft shell made from styrene-acrylonitrile, and comprise a hard styrene-acrylonitrile matrix and a hydrogenated copolymer made from styrene and butadiene. The films obtainable therefrom are very tough and tear-resistant. However, the flowability of the molding compositions is not always adequate for extrusion processing, and therefore the reliability of the extrusion process, and also the quality of the extruded film product, are not fully satisfactory.
EP-A 693 530 teaches improvement of the impact strength of mixtures made from polycarbonate and diene graft rubbers or alkyl acrylate graft rubbers, by using functionalized polyisobutylene polymers. In DE-A 20 20 478 polyisobutene (PIB), also termed polyisobutylene, is used concomitantly in blends made from thermoplastics to improve the dielectric properties of the molding composition.
In an Amoco company publication xe2x80x9cAmoco Polybutenexe2x80x9d which appeared in 1994 it is reported on page 18 that polybutene improves the impact strength and elasticity of a wide variety of thermoplastics. The Amoco company publication of June 1995 xe2x80x9cAcrylonitrile-Butadiene-Styrene Modification using Amoco Polybutenexe2x80x9d discloses on page 5 that polybutene improves the impact strength of ABS (acrylonitrile-butadiene-styrene).
It is not disclosed in any of the publications mentioned that polybutene considerably improves the flowability and therefore the extrusion performance of films made from ASA (acrylonitrile-styrene-acrylate).
It is an object of the present invention to overcome the disadvantages described at the outset. A particular object is to provide molding compositions which have good flowability and good extrusion properties and can be extruded with high reliability of the process to give films or moldings of consistent product quality, and also having good and well balanced mechanical properties.
We have found that this object is achieved by means of the thermoplastic molding compositions defined at the outset.
The invention provides, furthermore, the use of the polymer mixture for producing films and moldings, and also films and moldings made from these compositions.
Component A) is present in the novel molding compositions in a proportion of from 20 to 98% by weight, preferably from 40 to 90% by weight and particularly preferably from 50 to 82% by weight, based on the total of components A) to D). This component is a particulate graft copolymer which has been built up from an elastomeric graft core al) (soft component) and, grafted onto this, a shell a2) (hard component).
The graft core a1) is present in a proportion of from 30 to 90% by weight, preferably from 40 to 80% by weight and in particular from 50 to 75% by weight, based on component A).
The graft core a1) is obtained by polymerizing a monomer mixture made from, based on a1),
a11) from 80 to 99.99% by weight, preferably from 85 to 99.5% by weight and particularly preferably from 90 to 99% by weight, of a C1-C10-alkyl acrylate,
a12) from 0.01 to 20% by weight, preferably from 0.5 to 10% by weight and particularly preferably from 1 to 5% by weight, of at least one crosslinking monomer, and
a13) from 0 to 19.99% by weight, preferably from 0 to 5% by weight, of one or more other monomers.
Particularly suitable alkyl acrylates a11) are ethyl acrylate, 2-ethylhexyl acrylate and especially n-butyl acrylate.
Crosslinking monomers a12) are bi- or polyfunctional comonomers, such as butadiene and isoprene, divinyl esters of dicarboxylic acids, such as succinic acid or adipic acid, diallyl or divinyl ethers of dihydric alcohols, such as of ethylene glycol or of 1,4-butanediol, diesters of acrylic acid and methacrylic acid with the dihydric alcohols mentioned, 1,4-divinylbenzene or triallyl cyanurate. Particular preference is given to the acrylate of tricyclodecenyl alcohol, known as dihydrodicyclopentadienyl acrylate, and also to the allyl esters of acrylic and methacrylic acids.
Replacing some of the monomers a11) and a12) in the graft core a1) of the molding compositions there may also be other monomers a13) which vary the mechanical and thermal properties of the core within a certain range. Examples which may be mentioned of such monoethylenically unsaturated comonomers are:
vinylaromatic monomers, such as styrene or styrene derivatives of the formula I 
xe2x80x83where R1 and R2 are hydrogen or C1-C8-alkyl and n is 0, 1, 2 or 3;
acrylonitrile, methacrylonitrile;
acrylic acid, methacrylic acid, dicarboxylic acids, such as maleic and fumaric acids, and also the anhydrides of these, such as maleic anhydride;
nitrogen-functional monomers, such as dimethylaminoethyl acrylate, diethylaminoethyl acrylate, vinylimidazole, vinylpyrrolidone, vinylcaprolactam, vinylcarbazole, vinylaniline and acrylamide;
C1-C4-alkyl methacrylates, such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylaue and hydroxyethylmethacrylate;
aromatic and araliphatic esters of acrylic or methacrylic acid, such as phenyl acrylate, phenyl methacrylate, benzyl acrylate, benzyl methacrylate, 2-phenylethyl acrylate, 2-phenylethyl methacrylate, 2-phenoxyethyl acrylate and 2-phenoxyethyl methacrylate;
unsaturated ethers, such as vinyl methyl ether;
and also mixtures of these monomers.
The graft shell a2) is present in a proportion of from 10 to 70% by weight, preferably from 20 to 60% by weight and particularly preferably from 25 to 50% by weight, based on component A).
The graft shell a2) is obtained by polymerizing a monomer mixture made from, based on a2),
a21) from 50 to 100% by weight, preferably from 60 to 95% by weight and particularly preferably from 65 to 85% by weight, of a styrene compound of the formula I 
xe2x80x83where R1 and R2 are hydrogen or C1-C8-alkyl and n is 0, 1, 2 or 3,
a22) from 0 to 50% by weight, preferably from 0 to 40% by weight and particularly preferably from 5 to 35% by weight, of at least one monoethylenically unsaturated nitrile compound, and
a23) from 0 to 40% by weight, preferably from 0 to 20% by weight, of one or more other monomers.
The styrene compound used of the formula (I) (component a21)) is preferably styrene, xcex1-methylstyrene or a C1-C8-alkyl-ring-alkylated styrene, such as p-methylstyrene or tert-butylstyrene. Styrene is particularly preferred.
Possible monoethylenically unsaturated nitrile compounds a22) are acrylonitrile, methacrylonitrile and mixtures of these, in particular acrylonitrile.
Replacing some of the monomers a21) or a22) there may also be other comonomers a23) building up the shell a2). The recommendations made for component a13) also apply to component a23), and additional monomers which may be mentioned are maleic anhydride and N-substituted maleimides, such as N-methyl-, N-phenyl- and N-cyclohexylmaleimide. The use of these is preferred.
The graft shell a2) preferably has a structure made from styrene or from a mixture of from 65 to 85% by weight of styrene, the remainder being acrylonitrile.
The graft polymers A) are obtainable in a known manner, preferably by emulsion polymerization at from 30 to 80xc2x0 C. Examples of emulsifiers suitable for this are alkali metal salts of alkyl- or alkylarylsulfonic acids, or are alkyl sulfates, fatty alcohol sulfonates, salts of higher fatty acids having from 10 to 30 carbon atoms, sulfosuccinates, ether sulfonates or resin soaps. Alkali metal salts of alkylsulfonates or fatty acids having from 10 to 18 carbon atoms are preferred.
In preparing the dispersion it is preferable to use an amount of water sufficient to give the finished dispersion a solids content of from 20 to 50% by weight.
Possible polymerization initiators are preferably free-radical generators, such as peroxides, preferably peroxosulfates, such as potassium peroxodisulfate, and azo compounds, such as azodiisobutyronitrile. However, it is also possible to use redox systems, in particular those based on hydroperoxides, such as cumene hydroperoxide. Concomitant use may also be made of molecular weight regulators, such as ethylhexyl thioglycolate, tert-dodecyl mercaptan, terpinols or dimeric xcex1-methylstyrene.
To maintain a constant pH, preferably from 6 to 9, concomitant use may be made of buffer substances, such as Na2HPO4/NaH2PO4 or sodium hydrogencarbonate.
Emulsifiers, initiators, regulators and buffer substances are used in the usual amounts, and further details concerning this are therefore unnecessary.
The graft core a1) may particularly preferably also be prepared by polymerizing the monomers a11) to a13) in the presence of a finely divided latex made from elastomeric or hard polymers (known as the seed latex polymerization procedure). Use may be made, for example, of a seed latex made from crosslinked poly-n-butyl acrylate or from polystyrene.
It is also possible in principle to prepare the graft core a1) by a process other than emulsion polymerization, for example by bulk or solution polymerization, and subsequently to emulsify the resultant polymers. Microsuspension polymerization is also suitable, preferably using oil-soluble initiators, such as lauroyl peroxide or tert-butyl perpivalate. The processes for this are known.
The graft shell a2) may be prepared under the conditions used for preparing the graft core a1). The shell a2) may be prepared in one or more steps. It is possible, for example, firstly to polymerize styrene and/or xcex1-methylstyrene alone and then styrene and acrylonitrile in two steps in succession. Other details on the preparation of the graft polymers A) have been described in DE-OS 12 60 135 and 31 49 358.
The reaction conditions are preferably balanced in a manner known per se in such a way that the particulate graft polymers A have a very uniform diameter d50 in the range from 60 to 1500 nm, in particular from 150 to 1000 nm and very particularly from 200 to 700 nm.
In preparing the novel thermoplastic compositions it is also possible, instead of a single graft polymer A), to use a variety of these polymers, especially those with markedly different particle sizes. Mixtures of this type with bimodal size distribution can give advantages related to process technology during further processing. Suitable ranges of particles diameters are firstly from 60 to 200 nm and secondly from 300 to 1000 nm. A bimodal particle size distribution may be achieved, for example, by partial agglomeration, as described in DE-B 2 427 960.
Other suitable graft polymers are those having more than one soft and hard shells, e.g. of the structure a1)-a2)-a1)-a2) or a2)-a1)-a2), especially in cases where the particles are relatively large.
If there are any ungrafted polymers produced from the monomers a2) during the grafting, these amounts, which are generally less than 10% of a2), are counted as part of the weight of component A) and not of component B), which may have a structure made from the same monomers.
Component B) of the novel molding composition is present in a proportion of from 0.5 to 78.5% by weight, preferably from 5 to 50% by weight and particularly preferably from 10 to 30% by weight, based on the total of components A) to D). Constituent B) is a thermoplastic polymer which is composed of
b1) from 50 to 100% by weight, preferably from 60 to 95% by weight and particularly preferably from 65 to 85% by weight, of a styrene compound of the formula I 
xe2x80x83where R1 and R2 are hydrogen or C1-C8-alkyl and n is 0, 1, 2 or 3,
b2) from 0 to 50% by weight, preferably from 0 to 40% by weight and particularly preferably from 5 to 35% by weight, of at least one monoethylenically unsaturated nitrile compound, and
b3) from 0 to 40% by weight, preferably from 0 to 20% by weight, of one or more other monomers,
based in each case on component B). Possible monoethylenically unsaturated nitrile compounds b2) are acrylonitrile, methacrylonitrile and mixtures of these, in particular acrylonitrile. Possible monomers b3) are those which have been mentioned for component a13) and a23).
Molding compositions for producing films preferably comprise from 0.5 to 50% by weight of component B, based on the total of components A) to D).
Polymers B), which due to their principal components styrene and acrylonitrile are generally also known as SAN polymers, are known and are in some cases also available commercially. They generally have a viscosity number VN (determined in accordance with DIN 53 726 at 25xc2x0 C., 0.5% by weight in dimethylformamide) of from 40 to 160 ml/g, corresponding to an average molecular weight of from about 40000 to 2000000. They are obtained in a known manner by bulk, solution, suspension, precipitation or emulsion polymerization. Details of these processes are described, for example, in Kunststoffhandbuch, ed. R. Vieweg and G. Daumiller, Vol. V xe2x80x9cPolystyrolxe2x80x9d, Carl-Hanser-Verlag, Munich, 1969, pp. 118 ff.
In the case of the monomers a21) and/or b1) it is also possible, instead of the styrene compounds or in a mixture with them, to use C1-C8-alkyl acrylates and/or methacrylates, particularly those which derive from methanol, ethanol, n- or isopropanol, sec-, tert- or isobutanol, pentanol, hexanol, heptanol, octanol or 2-ethylhexanol, and particularly from n-butanol. Particular preference is given to methyl methacrylate.
The proportion of component C) in the molding compositions, based on the total of components A) to D), is from 1 to 79% by weight, preferably from 4.9 to 50% by weight and particularly preferably from 7.5 to 39.5% by weight. Component C) is a copolymer composed of
c1) from 30 to 90% by weight, preferably from 40 to 80% by weight and particularly preferably from 45 to 70% by weight, of styrene and/or xcex1-methylstyrene,
c2) from 10 to 70% by weight, preferably from 20 to 60% by weight and particularly preferably from 30 to 55% by weight, of butadiene, and
c3) from 0 to 20% by weight, preferably from 0 to 10% by weight, of one or more other monomers,
in which some or all of the olefinic double bonds have been hydrogenated.
Possible components c3) are any of the compounds which can be polymerized anionically, and also mixtures of these, in particular isoprene, alkyl methacrylates, such as methyl methacrylate and tert-butyl methacrylate, xcex1-methylstyrene, dimethylbutadiene, and particularly preferably ring-substituted styrenes and 1,1-diphenylethylene.
The copolymers C) are known and are also in some cases commercially available (e.g. Kraton(copyright) from Shell Chemicals and Glissoviscal(copyright) from BASF) and are obtainable in a manner known per se.
The copolymers are preferably prepared by anionic polymerization in solution. The initiators used are principally organometallic compounds, such as sec-butyllithium. The product of the anionic polymerization, as is generally desired, is a polymer which is essentially unbranched. If a mixture of styrene and butadiene is subjected to the polymerization, the polymers obtained, depending on the copolymerization conditions selected, have a characteristic distribution of the monomer units.
Preference should generally be given to block copolymers in which one chain end is formed from a block made from styrene and the other chain end is formed from a block made from butadiene. These blocks may be separated from one another by polymers with random distribution, and the blocks may also contain subordinate amounts of the respective other monomer.
If a mixture of styrene and butadiene is polymerized anionically with one of the initiators mentioned and concomitant use of small amounts of an ether, in particular tetrahydrofuran (THF) as a cocatalyst, the polymer chains produced have neither blocks nor a completely random distribution of the structural units. Rather, the proportion of one of the components increases along the chain in one direction and the proportion of the other component decreases in the same direction.
At the start of the polymerization it is preferable to incorporate butadiene, with a small amount of styrene, into the chains produced. They are therefore rich in butadiene. As the reaction proceeds and the reaction mixture therefore has a falling butadiene monomer content, styrene monomer molecules are increasingly polymerized, and the chain becomes richer in styrene, until finally after the butadiene has been entirely consumed a terminal segment is formed from homopolystyrene. Details of the process have been described in DE-A 31 06 959.
Other suitable polymers have a star-shaped structure, obtained by linking a number of polymer chains, principally of block copolymers of styrene block/butadiene block/styrene block (xe2x80x9cthree-block polymerxe2x80x9d) type, via polyfunctional molecules. Examples of suitable linking agents are polyepoxides, such as epoxidized linseed oil, polyisocyanates, such as 1,2,4-triisocyanatobenzene, polyketones, such as 1,3,6-hexanetrione and polyanhydrides, and also dicarboxylic esters, such as diethyl adipate, and silicon halides, such as SiCl4, metal halides, such as TiCl4 and polyvinylaromatics, such as divinylbenzenes. Further details of the preparation of these polymers may be found, for example, in DE-A 26 10 068.
The polymers C) mentioned may also comprise other copolymerized monomers c3), possible compounds for which are the anionically polymerizable compounds mentioned for c3).
Suitable solvents for the polymerization of the monomers c1) to c3) are anhydrous liquids, such as alkanes and cycloaliphatic and aromatic hydrocarbons. The use of cyclohexane is preferred.
The anionic polymerization is preferably carried out at from xe2x88x9220 to 150xc2x0 C.
The reaction is terminated in a known manner by adding a polar compound, such as water or an alcohol.
The hydrogenation of the olefinic double bonds still present in the polymer and deriving from butadiene is likewise carried out in a manner known per se, preferably in a homogeneous phase with hydrogen, using a soluble selective hydrogenation catalyst, such as a mixture of nickel(II) acetylacetonate and triisobutylaluminum in an inert solvent, such as hexane. The hydrogenation temperature is preferably from 20 to 200xc2x0 C. and it is advantageous to use a hydrogen pressure in the range from 6 to 30 bar. Complete hydrogenation of the nonaromatic double bonds is not necessary. Rather, a degree of hydrogenation of 95% is sufficient. More details on the hydrogenation may be found, for example, in the abovementioned DE-A 31 06 959.
The work-up to give the desired polymers, whose molecular weights may be adjusted by varying the temperature and duration of the polymerization, and also the amounts of monomers, preferably to from 50000 to 200000, in particular from 70000 to 120000, is carried out as usual by removing the hydrogenation catalyst and taking off the solvent, e.g. by direct devolatilization.
In the case of polymers with a terminal homopolystyrene block the proportion of component C) is from to 30% by weight, preferably from 7 to 25% by weight.
The proportion of component D) in the molding compositions, based on the total of components A) to D), is from 0.5 to 30% by weight, preferably from 0.1 to 20% by weight and in particular from 0.5 to 10% by weight. Component D) is a copolymer which is composed of
d1) from 50 to 100% by weight, preferably from 70 to 100% by weight and in particular from 80 to 100% by weight, of isobutene, and
d2) from 0 to 50% by weight, preferably from 0 to 30% by weight and in particular from 0 to 20% by weight, of one or more other monomers,
based in each case on D). Isobutene is also termed isobutylene. Possible comonomers d2) are: butene, styrene and styrene compounds of the formula I, such as xcex1-methylstyrene, isoprene, indene, butadiene, cyclopentadiene, and also vinyl- and vinylidene-terminated olefins, and the olefins known as internal olefins having from 3 to 14 carbon atoms, such as 2-methyl-2-pentene and 2-methyl-1-pentene, 2,4,4-trimethyl-2-pentene and 2,4,4-trimethyl-1-pentene, cis- and trans-2-butene, 1-butene, 1-hexene, 1-octene and 1-decene.
The polymers D) are usually termed polyisobutene (polyisobutylene or PIB), corresponding to their principal component isobutene (isobutylene). At room temperature, depending on the molecular weight, they are generally viscous-oily (average molecular weight {overscore (M)}N from about 300 to 600), oily-highly tacky ({overscore (M)}N from about 700 to 2000), highly viscous-highly tacky ({overscore (M)}N from about 2000 to 10000), highly viscous-low tack ({overscore (M)}N from about 10000 to 120000) to rubbery elastomeric ({overscore (M)}N from about 300000 to 2500000).
Depending on the product properties desired, the component D) used may be polyisobutene homo- or copolymers. The comonomer proportion d2) is preferably less than 20% by weight, based on D), and particular preference is given to the use of polyisobutene homopolymer.
As already mentioned, the polyisobutenes are usually characterized by molecular weight (e.g. as the number-average {overscore (M)}N). Polyisobutenes of very different molecular weights may be used as component D), in particular those with average molecular weights {overscore (M)}N in the range from 100 to 1000000, preferably from 100 to 100000, in particular from 500 to 10000.
The copolymers D) are known and commercially available, e.g. as Glissopal(copyright) (BASF), Hyvis(copyright) or Ultravis(copyright) (BP) or Indopol(copyright) (Amoco).
The polyisobutene homo- or copolymers (component D)) are generally prepared by cationic polymerization at low temperatures. These processes are known to the person skilled in the art and are described, for example, in U.S. Pat. No. 5,286,823 and in Kunststoff-Handbuch, Vol. VI Polyolefine, Carl Hanser Verlag, Munich, 1969, and in Ullmanns Encyclopadie der Technischen Chemie, 4th ed., Vol. 19, p. 216.
Besides components A), B), C) and D), the thermoplastic molding compositions may also comprise additives, such as lubricants, mold-release agents, pigments, dyes, flame retardants, antioxidants, stabilizers to protect against the action of light, fibrous or pulverulent fillers, fibrous or pulverulent reinforcing agents, and antistats, in the amounts usual for these agents.
The novel molding compositions may be prepared by mixing processes known per se, for example with melting in a mixing apparatus, e.g. in an extruder, Banbury mixer, kneader, roll mill or calender, at from 150 to 300xc2x0 C. However, the components may also be mixed xe2x80x9ccoldxe2x80x9d, without melting, and the mixture composed of powder or pellets not melted and homogenized until it is processed.
The molding compositions may be used to produce moldings of any type, in particular films. The films may be produced by extrusion, rolling or calendering, or other processes known to the person skilled in the art, usually at from 150 to 280xc2x0 C. Preference is given to the production of films from the molding compositions by extrusion. For this, the novel molding compositions are shaped to give a processable film, by heating and/or friction alone or with concomitant use of plasticizing or other additives. Extruders with slot dies, for example, are suitable for this. The films usually have a thickness of from 0.05 to 2 mm. The processing of films of this type to give finished products is carried out., for example, by thermoforming, usually at from 120 to 170xc2x0 C.
The novel molding compositions may also be used for coextrusion together with other polymers, giving coextruded moldings or coextruded films. Examples of other polymers of this type are acrylonitrile-butadiene-styrene (ABS), acrylonitrile-styrene-acrylate (ASA), polybutylene terephthalate or polyethylene terephthalate (PBT and PET, respectively), polyvinyl chloride (PVC), polystyrene-acrylonitrile (SAN), methyl methacrylate-ABS (MABS) and other commonly used thermoplastic polymers.
The films may be used in a wide variety of ways, for example in the automotive industry for construction of automobile interiors, for decorative uses, as a leather substitute in the production of cases and bags, and in the furniture industry as a covering material for laminating the surfaces of furniture.
The novel thermoplastic molding compositions contain no halogen, they are very substantially free from constituents which escape by evaporation or bleeding, and during processing they show virtually no disadvantageous changes, such as discoloration. In particular, even without concomitant use of appropriate stabilizers or other additives, they have excellent heat-aging resistance and light resistance, and also good mechanical properties.
In particular, the novel molding compositions have good flowability, especially during extrusion processing. The good extrusion properties of the molding compositions give rise to very consistent product quality in the films.